Yes let's put LEGO Horizon on Xbox, the console that is dying at retail across most of the world and has had a B2P sales collapse outside of a few exceptions the past 2-3 years. That's the only way to make the game a "commercial success"
Phil and the cronies are desperate to have Xbox in the narrative at any cost, no matter how ridiculous or unrealistic a rumor gets, and it's almost always something meant to be antagonistic towards PlayStation. That's how you know a brand is completely broken and insecure of its own identity.
SIE couldn't be stupid enough to do this without knowing it will
IMMEDIATELY open up conversation about the mainline Horizon and other major 1P AAA games getting Xbox ports, and that would be the only thing dominating discourse online. Even non-gaming media wouldn't shut up about it...does SIE really want those kind of optics for the brand? Those optics haven't been doing well for Xbox the past year but with them its out of necessity to survive as a gaming brand.
PlayStation doesn't need to make a similar move to survive; if they did it it'd only be out of profit-driven greed which will always bite them in the ass later on. So I'm not buying there's any credibility to this rumor, other than some bored nobody with a slight-passing credential putting it out there. If it turns out to be real though, then the can of worms is opened, and SIE will FAFO.